Locomotive-boiler fire-box.



F. P. (mums. LOGOM OTIVE BOILER FIRE BOX.

APPLIOATIOH TILED OOT.13. 1013.

Patented Nov. 24, 1914 UNITED STATES PATENT OFFICE.

FREDERICK IF. GAINES, OF SAVANNAH, GEORGIA, ASSIGNOR TO AMERICAN ARCH COMPANY, OF NEW YORK, N. Y., A CORPORATION OFNEW YORK.

LOGOMOTIVE-BOILER FIRE-BOX.

Specification of Letters Patent. I Patented Nov, 24,1914.

Application filed October 133, i913. Serial No. 794,910.

To all whom it may concern Be it known that I, FREDERICK F. Games, a citizen of the United dent of Savannah, county of Chatham, and State of Georgia, have invented certain new and useful Improvements in Locomotive- Boiler Fire-Boxes, of which the following is a specification.

My invention relates to improvements in locomotive boilers and has particular reference to improvements in locomotive boiler fireboxes.

The object of my invention is to increase the efiiciency of locomotive boiler fireboxes; to prevent the direct flow of the products of combustion from the fuel bed to the flues, and to provide an auxiliary combustion chamber of relatively large dimensions without encroaching upon the grate area.

A further object of m invention is to provide a refractory ba e wall of simple construction adapted to be interposed between the fuel bed and the flues in locomotive boilers of the extension combustion chamber type; to provide means whereby air may be admitted to the fireboxabove the fuel bed in fireboxes of said type, and to provide means whereby the cinders which accumulate in the auxiliary combustion chamber can be easlly removed.

My invention consists in a locomotive boiler firebox of the extension combustion chamber type provided with a refractory baflie wall erected in the mouth of the extension, and water circulating tubes rising from the floor of the extension and inclined upwardly and rearwardly through the firebox and serving to support the wall.

My invention also consists in a construction as abov described, in combination with air inlet thimbles arranged at the rear end of the extension and beneath the wall, and adapted to admit air to air conduits rising through the wall and by which air is ad mitted to the firebox above the fuel bed.

My invention also consists in a locomotive boiler firebox 'of the extension combustion chamber type. in combination with watercirculating tubes rising from the lower part 'of the rear end of the extension, and inclined upwardly and rearwardly to the rear end of the firebox, a refractory wall rising from the floor of the extension, and inclined upwardly and rearwardly in thefirebox resting on and supported by said tubes, said tates, and a resie wall having vertically arranged air inlet passages, and cooperating air inlet thimbles arranged in the lower part of the extension extending through the water space of the,

boiler and adapted to admit air to the passages in the wall and 'a cinder outlet arranged between the wall and the flue sheet and also extending through the lower water nal section of a firebox of the extension com-- bustion chamber type embodying my invention; Fig. 2 is a-vertical, transverse section of the firebox on the line 2-2 of Fig. 1; Fig. 3 is a detail transverse section of the firebox on the line 3-3 of Fig. 1; and

Fig. 4: is a transverse detail section of the refractory arch on the line 4'4 of Fig. 1.

With the advance in the development of locomotives in order to provide capacity commensurate with the modern developments of transportation it has been found desirable and necessary to extend the combustion chamber of the firebox forwardly into the barrel orbody of the boiler, placing the flue sheet some distance in advance of the forward end of the grate so that sufficient space shall be provided in the firebox for the purpose of completing the combustion of the fuel before thegases escape through the fines, and in order to cause the burning of sufiicient fuel to produce the necessary power it has been found necessary to create a very strong artificial draft so that suflicient air may be drawn into the firebox for this excessively high rate of combustion. This exceedingly strong draft serves to cause the gaseous products of combustion to flow in substantially a direct path from the fuel bed to the fines and thereby the rear part of the firebox, and particularly the rear portion of the crown sheet, does not receive its due proportion of. heat and consequently the firebox is not operated to its maximum efiiciency. For the purpose, among others, of preventing this direct flow of the gases of combustion'from I 5 the fuel bedto thefiues and to cause them .to flow backward and forward through the firebox in contact with all of the interior surface thereof, I provide a refractory bafiie wall arranged in the path of the gases, and

in fireboxes of the extension combustion chamber type 1 preferably build this wall in the rear end of the extension, inclining it rearwardly and upwardly over the, forward end of the grates, whereby the rising firebox gases'are forced rearwardly in the firebox in order to rise past the rear end of the. battle wall so that they may flow forwardly "along the crown sheet to the forward end of the firebox where they escape through the flues.

For the purpose of supporting the Wallin this position, T provide Water-circulating tubes which rise from the rear ,part of the floor of the extension and are inclined up Wardly and rearwardly through the firebox to the upper part of the rear sheet. The wall rests upon these tubes and is supported by .them in inclined position.

- For the; purpose of enhancing. the eficiency of the firebox, ll provide the wall with air inlet passages which rise from the lower end thereof, and I provide in the lower part of the rear end of the extension air inlet thimbles which extend through the immediate surrounding water space and admit air to the lower ends of the said air inlet passages. These passages rise upwardly through the wall and open through the rear face thereof adjacent to its upper end and 40 thereby inject air into the rising burning fixebox gases above the fuel bed. In some boilers I add to the wall the beneficial effects of a transverse refractory arch which extends from the rear upper end of the wall rearwardly and upwardly in the firebox, and

which is also supported by said tubes. This arch serves to cause the firebox gases to flow rearwardly in the firebox and also serves to effect the admixture of the admitted air i with the rising firebox gases and thereby produce substantially complete combustion before the gases escape from the firebox. The refractory wall, as thus described, divides the extension of the combustion chamber' of the firebox from the main portion thereof and, forms in reality an auxiliary combustion chamber connected with the combustion chamber by the passage between the upper-part of the wall and the o crown sheet, andthis auxiliary combustion chamber not only serves to permit the completion of combustion in a space which is protected from the entrance of cold air" at times when the fuel doors are opened, but b5 also serves as a chamber in which the gases nuaeae of combustion may expand and thus reduce their rate of flow, which, in turn, causes the gases of combustion to lose or drop their burden of cinders or other unburned fuel particles which the strong draft used in such furnaces causes the rising gases to lift from the fuel bed, and consequently these fuel particles are prevented from enteringing of a refractory wall in the manner described is an exceedingly simple operation, once the water-circulating tubes have been installed, it is only necessary to provide bricks of suitable shape to fit the curvature of the floor of the extension and place these bricks in position on the floor and against the tubes.

A firebox A of the type described, as

shown in the drawings, is provided with a barrel-like extension a at its forward end which is closed at its forward end by means of a flue sheet a". This barrel-like extension at its upper part merges intothe crown sheet a of the firebox and at its sides into the side sheets a of the firebox, its lower part joins the rear wall a of the forward water leg at and thus completes the forward end of the firebox. The rear end of the firebox is closed by the rear sheet a Flues a lead forward from the flue sheet and the firebox is provided with a grate a of the usual construction Which'extends between the front water leg a? and the rear water leg a The rear end of the'firebox is pro vided with a fuel door or opening a.

In the employment of my invention shown in the drawings, 1 provide a group of water-circulating tubes B, which rise from the rear part of thefloor of the extension, are inclined upwardly and rearwardly for a short distance at an angle of substantially 45' degrees and then extend upwardly and rearwardly to the rear end of the firebox.

These tubes serve the purpose of permitting a rapid circulation or interchange of the water of the boiler from the lower part to the upper part and thereby serve to bring a verylarge quantity of water into the best position for receiving heat from the burning gases as they extend through substan; tially the hottest area of the burning The firebox as described has a water space (1" below the floor. a of the extension, and this water space merges at its rear end into the front water leg a".

I make use of the tubes B to support a refractor wall C. This wall rests at its lower en upon the floor a of the extension and has its rear face in contact with the tubes B. It is inclined upwardly and rear- Wardly conforming with the inclination of the tubes andextends over the forward end of thegrate. I preferably build this wall of a plurality of horizontal rows of bricks which extend transversely across the firebox at this pointand to the extent of the height of the wall completely close ofi the space between the wall and flue sheet forming an auxiliary combustion chamber a and dividing it from the main combustion chamber a which occupies the space above the grate and in the rear portion of the firebox. The combustion chamber a is thus protected from the entrance of air and one side of it being composed of the refractory wall C, the chamber can be maintained at a high temperature in which the firebox gases can complete their combustion before they enter the flues.

In order to prevent the displacement of the wall, I sometimes provide lugs 0 projecting upwardly fromthe floor a of the auxiliary combustion chamber and adapted to contact with the forward face of the lower tier of bricks and hold them in position against the tubes B. Furthermore, I preferably provide the upper sides of the bricks a with central projections a and on their lower faces with cooperating grooves 0 so that the several transverse rows of brick, when in position, are interlocked at their meeting faces and thus serve to mutually retain each other in position.

For 'the purpose of enhancing the efliciency of the firebox, I provide air inlet passages 0 extending upwardly through the wall, and to admit air to these passages I provide air inlet thimbles or tubes 0 which project through the water space a" into the lower part of the auxiliary combustion chamber a arranged to cooperate with the air conduits or passages 0. That is, they register with the lower ends of these passages and thereby air is admitted from beneath the extension to said passages in the wall. At the upper end of the wall I provide lateral passages c which join with the upper ends of the vertical passages c and permit the air which rises through these conduits or passa es to escape into the ,main combustion cham er a above the fuel bed in position to be intermingled and mixed with the firebox ases as they rise therein. As thus described, the wall is sufficient in extent to produce the desired results, but under some conditions it is advantageous and I prefer to add to the wall what may be termed a front arch D, which extends from the rear or upper end of the wall C 5 rearwardly and upwardly through the firebox, and thus causes the rising fire box gases to flow closer to the rear end of the firebox. In thus flowing rearwardly beneath the arch, the air, which is admitted through the wall, is caused to be more thoroughly mixed and mingled with the gases and thereby enhance the burning of the fuel; Preferably I form the arch of a number of transverse rows of or bricks d which are of suflicient length to span from tube to tube resting at their ends thereon and bein supported thereby. In the illustration 0% my 1nvention I have shown this archas being composed of four transverse rows of bricks, but 1t will be .understood that the arch. may be made to extend any desired distance rearwardly from the upper end of the wall so that the desired results may be attained.

As hereinbefore explained, I provide a cinder outlet E entering the lower part of the auxiliary combustion chamber and arranged betwcen the wall and the flue sheet. As illustrated, this outlet comprises a tube 6 joined at its upper end to the floor a" of the auxiliary combustion chamber, and at its lower end to the outer wall or shell a" of the boiler. It extends through the water space a" and permits easy access to the auxiliary combustion chamber a. To prevent the free air from enterin the auxiliary combustion chamber throng the cinder hopper I provide the lower end of the cinder hopper with a removable cover 6 which is adapted to be readily opened for the purpose of removing the cinders or other parti clcs which collect within the hopper E. For the purpose of causing the collecting cinders to gravitate into the hopper, I provide the lower part of the auxiliary combustion chamber with a hoppered bottom filling it from the margin of the outlet E to the walls of the combustion chamber by means of refractory material and thereby roviding an inclined ho pered floor a". he refractory wall, as tiius constructed, does not prevent access to the flue sheet. at times when it is necessary to repair the fines, and if it is necessary to repair the stay bolts the side portions of the arch and of the wall may readily be removed for this purpose. Preferably I build both the wall and the arch of bricks which are not too large to be passed through the fuel door so that'the arch and the wall may be readily repaired without the necessity of removing portions of the grate.

As many modifications of my invention will readily suggest themselves to one skilled in the art, I do not limit or confine my invention to the specific structures herein shown and described.

I claim:

1. A locomotive boiler firebox havin a barrel-like extension at its forward end%)eyond the forward end of the grate which extension is closed at its forward end by the flue sheet, waterzcirculating tubes rising from the rear part of said extension and extending upwardly and rearwardly through 1 the firebox, a refractory wall arranged in ranged: in the lower part of the boiler beneath saidwall adapted to admit airto said passages and a cinder opening or outlet also arranged in the lower part of the boiler and between the Wall and the flue sheet adapted to permit the easy removal of cinders fromthis space and a removable cover normally closing the lowerend' of the out-a let.

2. In a locomotive boiler firebox a barrellike extension extending i'forwardlyinto the boiler beyond the front end of the grates,

said extension being closedlat its forward end by the flue sheet, water-"circulating tubes rising from the floor of the-extension adjacent the rear endrthereof and extending up ward-1y and rearwardly through the the box, a refractory wall resting on the lower part of the extension and supported in inclined position by the tubes, a refractory arch extending rearwardly through the firebox from the upper end of said wall and also supported by said tubes, a cinder outlet arranged in the lower part of the boiler between the wall and the flue sheet and.

adapted to-permit the easy removal of cinders from the firebox extension.

lln testimony whereof, I have hereunto set my hand, this 1st dayof Oct, 1913, in the two subscribing witnesses.

. FREDERICK 1F. GrAllNlES.

Witnesses:

'J. lit; Konnrnn, W. E. DAVIS.

presence of 

